<head>
  <style> body { margin: 0; } </style>

  <script src="//unpkg.com/force-graph"></script>
  <!--<script src="../../dist/force-graph.js"></script>-->
</head>

<body>
  <div id="graph"></div>

  <script>
    // Random tree
    const N = 300;
    const gData = {
      nodes: [...Array(N).keys()].map(i => ({ id: i })),
      links: [...Array(N).keys()]
        .filter(id => id)
        .map(id => ({
          source: id,
          target: Math.round(Math.random() * (id-1))
        }))
    };

    const Graph = new ForceGraph()
      (document.getElementById('graph'))
        .linkDirectionalParticles(2)
        .graphData(gData);
  </script>
</body>